Stimulating TRPM7 suppresses cancer cell proliferation and metastasis by inhibiting autophagy

Targeting TRPs in autophagy regulation and human diseases

Transient receptor potential channels (TRPs) are widely recognized as a group of ion channels involved in various sensory perceptions, such as temperature, taste, pressure, and vision. While macroautophagy (hereafter referred to as autophagy) is primarily regulated by core machinery, the ion exchange mediated by TRPs between intracellular and extracellular compartments, as well as within organelles and the cytoplasm, plays a crucial role in autophagy regulation as an important signaling transduction mechanism. Moreover, certain TRPs can directly interact with autophagy regulatory proteins to participate in autophagy regulation. In this article, we provide an in-depth review of the current understanding of the regulatory mechanisms of autophagy, with a specific focus on TRPs. Furthermore, we highlight the potential prospects for drug development targeting TRPs in autophagy for the treatment of human diseases.

MCOLN1/TRPML1 in the lysosome: a promising target for autophagy modulation in diverse diseases

MCOLN1/TRPML1 is a nonselective cationic channel specifically localized to the late endosome and lysosome. With its property of mediating the release of several divalent cations such as Ca2+, Zn2+ and Fe2+ from the lysosome to the cytosol, MCOLN1 plays a pivotal role in regulating a variety of cellular events including endocytosis, exocytosis, lysosomal biogenesis, lysosome reformation, and especially in Macroautophagy/autophagy. Autophagy is a highly conserved catabolic process that maintains cytoplasmic integrity by removing superfluous proteins and damaged organelles. Acting as the terminal compartments, lysosomes are crucial for the completion of the autophagy process. This review delves into the emerging role of MCOLN1 in controlling the autophagic process by regulating lysosomal ionic homeostasis, thereby governing the fundamental functions of lysosomes. Furthermore, this review summarizes the physiological relevance as well as molecular mechanisms through which MCOLN1 orchestrates autophagy, consequently influencing mitochondria turnover, cell apoptosis and migration. In addition, we have illustrated the implications of MCOLN1-regulated autophagy in the pathological process of cancer and myocardial ischemia-reperfusion (I/R) injury. In summary, given the involvement of MCOLN1-mediated autophagy in the pathogenesis of cancer and myocardial I/R injury, targeting MCOLN1 May provide clues for developing new therapeutic strategies for the treatment of these diseases. Exploring the regulation of MCOLN1-mediated autophagy in diverse diseases contexts will surely broaden our understanding of this pathway and offer its potential as a promising drug target.Abbreviation: CCCP:carbonyl cyanide3-chlorophenylhydrazone; CQ:chloroquine; HCQ: hydroxychloroquine;I/R: ischemia-reperfusion; MAP1LC3/LC3:microtubule associated protein 1 light chain 3; MCOLN1/TRPML1:mucolipin TRP cation channel 1; MLIV: mucolipidosis type IV; MTORC1:MTOR complex 1; ROS: reactive oxygenspecies; SQSTM1/p62: sequestosome 1.

SNARE proteins: Core engines of membrane fusion in cancer

Vesicles are loaded with a variety of cargoes, including membrane proteins, secreted proteins, signaling molecules, and various enzymes, etc. Not surprisingly, vesicle transport is essential for proper cellular life activities including growth, division, movement and cellular communication. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) mediate membrane fusion of vesicles with their target compartments that is fundamental for cargo delivery. Recent studies have shown that multiple SNARE family members are aberrantly expressed in human cancers and actively contribute to malignant proliferation, invasion, metastasis, immune evasion and treatment resistance. Here, the localization and function of SNARE proteins in eukaryotic cells are firstly mapped. Then we summarize the expression and regulation of SNAREs in cancer, and describe their contribution to cancer progression and mechanisms, and finally we propose engineering botulinum toxin as a strategy to target SNAREs for cancer treatment.

OIP5-AS1/CD147/TRPM7 axis promotes gastric cancer metastasis by regulating apoptosis related PI3K-Akt signaling

Background

To explore the mechanism of OIP5-AS1/CD147/TRPM7 axis to gastric cancer (GC) metastasis.

Methods

Bioinformatic analysis was performed to pick up the candidate genes associated with regulation GC metastasis. Using GC cell lines, AGS and MKN-45 as research objects, identify the effect of candidate genes on GC metastasis, judge cell proliferation status by MTT assay and cell clone number, and detect cell migration by Transwell and Wound-healing assay. The molecular mechanism of CD147/OIP5/TRPM7 axis regulating GC metastasis was further explored by RNA sequencing. The key signaling pathways were subsequently verified by flow cytometry and WB.

Results

Bioinformatic analysis suggested OIP5-AS1/CD147/TRPM7 axis may be involving in GC metastasis. The RNA interference experiment proved that after gene interference, the proliferation ability of GC cells decreased significantly (P<0.05), which was manifested in the reduction of the number of cell clones. In addition, the migration ability of GC cells was also affected, which was based on the results of Wound Healing (P<0.05). CD147, OIP5-AS1 and TRPM7 all have harmful effects on GC cells. The relationship between OIP5-AS1 and CD147/TRPM7 was detected by RNA immunoprecipitation. Moreover, the RNA sequencing data indicated that CD147/OIP5-AS1/TRPM7 may coordinately regulate the PI3K-AKT pathway related to GC cell apoptosis, thereby affecting the proliferation and migration of GC cells. After RNA interference, the level of apoptosis increased both in AGS and MKN-45 cells. Meanwhile, the expression of pro-apoptotic proteins Caspase9 and BAX were up-regulated (P<0.05). In addition, the expression of PI3K and AKT proteins was reduced (P<0.05). The mouse tumorigenesis experiment corroborated the results of the in vitro study.

Conclusion

OIP5-AS1/CD147/TRPM7 axis reduces GC cell proliferation by regulating apoptosis associated with PI3K-AKT signaling, further affecting cancer metastasis.

DNA Sensor-Based Strategy to Visualize the TRPM7 mRNA-Mg2+ Signaling Pathway in Cancer Cells

Technological advances and methodological innovations in cell signaling pathway analysis will facilitate progress in understanding biological processes, intervening in diseases, and screening drugs. In this work, an elaborate strategy for visualizing and monitoring the transient receptor potential melastatin 7 (TRPM7)-Mg2+ signaling pathway in living cells was constructed through the logical analysis of upstream mRNA and downstream molecules by two individual DNA sensors. The DNA sensors are constructed by modifying the dye-labeled DNA sequences on the surface of gold nanoparticles. By hybridizing with upstream mRNA, Cy5-modified DNA sensor 1 can detect and silence it simultaneously, outputting a red fluorescence signal. When the upstream mRNA is silenced, the concentration of downstream molecules of Mg2+ will be affected and down-regulated. The FAM-modified DNA sensor 2 detects this change and emits a green fluorescence as a signal. Therefore, the dynamic information on TRPM7 mRNA and the Mg2+-mediated signaling pathway can be successfully obtained by fluorescence imaging methods. Furthermore, the TRPM7 mRNA-Mg2+ signaling pathway also affects cell activity and migratory function through cell scratching and other experiments. More importantly, the proposed sensor also shows potential for screening signaling pathway inhibitors. Our work provides a simple and general strategy for the visualization of signaling pathways, which helps to understand the changes in the physiological activities of cancer cells and the causes of carcinogenesis and is crucial for cancer diagnosis and prognosis.

TRP (transient receptor potential) ion channel family: structures, biological functions and therapeutic interventions for diseases

Transient receptor potential (TRP) channels are sensors for a variety of cellular and environmental signals. Mammals express a total of 28 different TRP channel proteins, which can be divided into seven subfamilies based on amino acid sequence homology: TRPA (Ankyrin), TRPC (Canonical), TRPM (Melastatin), TRPML (Mucolipin), TRPN (NO-mechano-potential, NOMP), TRPP (Polycystin), TRPV (Vanilloid). They are a class of ion channels found in numerous tissues and cell types and are permeable to a wide range of cations such as Ca²⁺, Mg²⁺, Na⁺, K⁺, and others. TRP channels are responsible for various sensory responses including heat, cold, pain, stress, vision and taste and can be activated by a number of stimuli. Their predominantly location on the cell surface, their interaction with numerous physiological signaling pathways, and the unique crystal structure of TRP channels make TRPs attractive drug targets and implicate them in the treatment of a wide range of diseases. Here, we review the history of TRP channel discovery, summarize the structures and functions of the TRP ion channel family, and highlight the current understanding of the role of TRP channels in the pathogenesis of human disease. Most importantly, we describe TRP channel-related drug discovery, therapeutic interventions for diseases and the limitations of targeting TRP channels in potential clinical applications.

TRP Channels in Tumoral Processes Mediated by Oxidative Stress and Inflammation

The channels from the superfamily of transient receptor potential (TRP) activated by reactive oxygen species (ROS) can be defined as redox channels. Those with the best exposure of the cysteine residues and, hence, the most sensitive to oxidative stress are TRPC4, TRPC5, TRPV1, TRPV4, and TRPA1, while others, such as TRPC3, TRPM2, and TRPM7, are indirectly activated by ROS. Furthermore, activation by ROS has different effects on the tumorigenic process: some TRP channels may, upon activation, stimulate proliferation, apoptosis, or migration of cancer cells, while others inhibit these processes, depending on the cancer type, tumoral microenvironment, and, finally, on the methods used for evaluation. Therefore, using these polymodal proteins as therapeutic targets is still an unmet need, despite their draggability and modulation by simple and mostly unharmful compounds. This review intended to create some cellular models of the interaction between oxidative stress, TRP channels, and inflammation. Although somewhat crosstalk between the three actors was rather theoretical, we intended to gather the recently published data and proposed pathways of cancer inhibition using modulators of TRP proteins, hoping that the experimental data corroborated clinical information may finally bring the results from the bench to the bedside.

TRPM7 mediates endoplasmic reticulum stress and ferroptosis in sepsis-induced myocardial injury

Transient receptor potential melastatin 7 (TRPM7), a non-selective cation channel, was significantly upregulated in the blood of patients with sepsis. This study focuses on the preliminary exploration of the probable regulatory mechanism of TRPM7 in sepsis-induced myocardial injury (SIMI). HL-1 cardiac muscle cell line was treated with lipopolysaccharide (LPS) to mimic SIMI in vitro, and TRPM7 level was assessed. The impacts of TRPM7 knockdown on cellular inflammation response, oxidative stress, apoptosis, endoplasmic reticulum (ER) stress, and ferroptosis were identified. In order to explore the mechanism, ER stress agonist tunicamycin (TM) or ferroptosis inducer erastin was applied to treat HL-1 cells. The influences of TM and erastin on the aforementioned aspects were evaluated. TRPM7 was elevated in response to LPS stimulation, and its knockdown reduced the secretion of inflammatory factors and oxidative stress degree. Moreover, TRPM7 knockdown significantly suppressed cell apoptosis, ER stress, and ferroptosis. TM and erastin reversed the functions of TRPM7 knockdown, indicating ER stress and ferroptosis mediated in the regulation of TRPM7. This research proposes the possibility of TRPM7 as a marker or target for SIMI, and provides theoretical support for follow-up research.

Carvacrol enhances anti-tumor activity and mitigates cardiotoxicity of sorafenib in thioacetamide-induced hepatocellular carcinoma model through inhibiting TRPM7

AIMS

Sorafenib (Sora) represents one of the few effective drugs for the treatment of advanced hepatocellular carcinoma (HCC), while resistance and cardiotoxicity limit its therapeutic efficacy. This study investigated the effect of transient receptor potential melastatin 7 (TRPM7) inhibitor, carvacrol (CARV), on overcoming Sora resistance and cardiotoxicity in thioacetamide (TAA) induced HCC in rats.

MATERIALS AND METHODS

TAA (200 mg/kg/twice weekly, intraperitoneal) was administered for 16 weeks to induce HCC. Rats were treated with Sora (10 mg/Kg/day; orally) and CARV (15 mg/kg/day; orally) alone or in combination, for six weeks after HCC induction. Liver and heart functions, antioxidant capacity, and histopathology were performed. Apoptosis, proliferation, angiogenesis, metastasis, and drug resistance were assessed by quantitative real time polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry.

KEY FINDINGS

CARV/Sora combination significantly improved survival rate, and liver functions, reduced Alpha-Fetoprotein level, and attenuated HCC progression compared with Sora group. CARV coadministration almost obviated Sora-induced changes in cardiac and hepatic tissues. The CARV/Sora combination suppressed drug resistance and stemness by downregulating ATP-binding cassette subfamily G member 2, NOTCH1, Spalt like transcription factor 4, and CD133. CARV boosted Sora antiproliferative and apoptotic activities by decreasing cyclin D1 and B-cell leukemia/lymphoma 2 and increasing BCL2-Associated X and caspase-3.

SIGNIFICANCE

CARV/Sora is a promising combination for tumor suppression and overcoming Sora resistance and cardiotoxicity in HCC by modulating TRPM7. To our best knowledge, this study represents the first study to investigate the efficiency of CARV/ Sora on the HCC rat model. Moreover, no previous studies have reported the effect of inhibiting TRPM7 on HCC.

On the modulation of TRPM channels: Current perspectives and anticancer therapeutic implications

The transient melastatin receptor potential (TRPM) ion channel subfamily functions as cellular sensors and transducers of critical biological signal pathways by regulating ion homeostasis. Some members of TRPM have been cloned from cancerous tissues, and their abnormal expressions in various solid malignancies have been correlated with cancer cell growth, survival, or death. Recent evidence also highlights the mechanisms underlying the role of TRPMs in tumor epithelial-mesenchymal transition (EMT), autophagy, and cancer metabolic reprogramming. These implications support TRPM channels as potential molecular targets and their modulation as an innovative therapeutic approach against cancer. Here, we discuss the general characteristics of the different TRPMs, focusing on current knowledge about the connection between TRPM channels and critical features of cancer. We also cover TRPM modulators used as pharmaceutical tools in biological trials and an indication of the only clinical trial with a TRPM modulator about cancer. To conclude, the authors describe the prospects for TRPM channels in oncology.

A pan-cancer-bioinformatic-based literature review of TRPM7 in cancers

TRPM7, a divalent cation-selective channel with kinase domains, has been widely reported to potentially affect cancers. In this study, we conducted multiple bioinformatic analyses based on open databases and reviewed articles that provided evidence for the effects of TRPM7 on cancers. The purposes of this paper are 1) to provide a pan-cancer overview of TRPM7 in cancers; 2) to summarize evidence of TRPM7 effects on cancers; 3) to identify potential future studies of TRPM7 in cancer. Bioinformatics analysis revealed that no cancer-related TRPM7 mutation was found. TRPM7 is aberrantly expressed in most cancer types but the cancer-noncancer expression pattern varies across cancer types. TRPM7 was not associated with survival, TMB, or cancer stemness in most cancer types. TRPM7 affected drug sensitivity and tumor immunity in some cancer types. The in vitro evidence, preclinical in vivo evidence, and clinical evidence for TRPM7 effects on cancers as well as TRPM7 kinase substrate and TRPM7-targeting drugs associated with cancers were summarized to facilitate comparison. We matched the bioinformatics evidence to literature evidence, thereby unveiling potential avenues for future investigation of TRPM7 in cancers. We believe that this paper will help orient research toward important and relevant aspects of the role of TRPM7 in cancers.

The Role of the Metabolism of Zinc and Manganese Ions in Human Cancerogenesis

Metal ion homeostasis is fundamental for life. Specifically, transition metals iron, manganese and zinc play a pivotal role in mitochondrial metabolism and energy generation, anti-oxidation defense, transcriptional regulation and the immune response. The misregulation of expression or mutations in ion carriers and the corresponding changes in Mn²⁺ and Zn²⁺ levels suggest that these ions play a pivotal role in cancer progression. Moreover, coordinated changes in Mn²⁺ and Zn²⁺ ion carriers have been detected, suggesting that particular mechanisms influenced by both ions might be required for the growth of cancer cells, metastasis and immune evasion. Here, we present a review of zinc and manganese pathophysiology suggesting that these ions might cooperatively regulate cancerogenesis. Zn and Mn effects converge on mitochondria-induced apoptosis, transcriptional regulation and the cGAS-STING signaling pathway, mediating the immune response. Both Zn and Mn influence cancer progression and impact treatment efficacy in animal models and clinical trials. We predict that novel strategies targeting the regulation of both Zn and Mn in cancer will complement current therapeutic strategies.

Mechanism of cell death pathways in status epilepticus and related therapeutic agents

The most severe form of epilepsy, status epilepticus (SE), causes brain damage and results in the development of recurring seizures. Currently, the management of SE remains a clinical challenge because patients do not respond adequately to conventional treatments. Evidence suggests that neural cell death worsens the occurrence and progression of SE. The main forms of cell death are apoptosis, necroptosis, pyroptosis, and ferroptosis. Herein, these mechanisms of neuronal death in relation to SE and the alleviation of SE by potential modulators that target neuronal death have been reviewed. An understanding of these pathways and their possible roles in SE may assist in the development of SE therapies and in the discovery of new agents.